kGamma            628 third_party/libwebp/enc/picture.c           (uint16_t)(pow(v / 255., kGamma) * kGammaScale + .5);
kGamma            632 third_party/libwebp/enc/picture.c       kLinearToGammaTab[v] = (int)(pow(x, 1. / kGamma) * 255. + .5);